This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A109270 #24 Aug 31 2025 03:48:09
%S A109270 4,6,10,11,14,16,17,20,22,24,26,28,30,31,36,38,39,40,45,48,50,52,54,
%T A109270 56,57,59,62,65,66,67,70,73,74,76,79,81,84,85,87,90,91,94,95,96,97,99,
%U A109270 100,104,105,106,109,110,111,114,115,116,120,122,123,124,125,126,130,134
%N A109270 Numbers k such that k^2 > (1/2)*(prevprime(k^2) + nextprime(k^2)).
%C A109270 One may call these k^2 the "strong squares" by analogy with A051634 (strong primes).
%e A109270 4^2=16>(13+17)/2 so 4 is a term;
%e A109270 5^2 < (23+29)/2=26, so 5 is not a term;
%e A109270 6^2=36>(31+37)/2 so 6 is a term, etc.
%p A109270 a:=proc(n) if n^2 > (1/2)*(prevprime(n^2)+nextprime(n^2)) then n else fi end: seq(a(n),n=2..150); # _Emeric Deutsch_, Jun 26 2005
%t A109270 prQ[n_]:=Module[{n2=n^2},n2>(NextPrime[n2]+NextPrime[n2,-1])/2]; Select[ Range[2,150],prQ] (* _Harvey P. Dale_, Feb 19 2012 *)
%Y A109270 Cf. A051634, A033597, A075190, A109269.
%Y A109270 Cf. A024675.
%K A109270 nonn,changed
%O A109270 1,1
%A A109270 _Zak Seidov_, Jun 24 2005
%E A109270 More terms from _Emeric Deutsch_, Jun 26 2005